Then, in their 30s, the patient kids were living Leave It to Beaver-like lives of happiness and success, and the impatient kids were more likely to be fat, unhappy drug addicts. So the researchers decided to scan their subjects' brains to see what was going on up there. Apparently, the patient subjects had a lot of prefrontal cortex activity, meaning they had greater control over social behavior and planning. The scans of the impatient kids showed more activity in the ventral striatum, the portion of the brain commonly linked with addiction.

So, if you want to predict the futures of the 4- to 6-year-old children in your life, tell them to not eat a marshmallow for 15 minutes. If they don't eat it, continue pumping cash into their college funds. If they do, just go ahead and buy that speedboat you've always wanted.

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Use it to flee the greedy crotchspawn you unleashed upon the world.

And this was a huge study, too -- 10,419 children all together. The Institute for Social and Economic Research found that "schedule-fed babies performed around 17 percent of a standard deviation below demand-fed babies in standardized tests at all ages, and four points lower in IQ tests at age 8 years."

And yes, before you ask, this proved still to be true after the study had corrected for socially disadvantaged kids and mothers who couldn't afford to feed their kids until they started trying to eat the bars of their cribs. In fact, poor kids scored the same advantage as rich kids who were just as demanding.

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"Look, I can use this to order some food, or I can just start eating the money itself. I'm a baby, I don't give a fuck."

Author and psychologist Penelope Leach says it has to do with the development of the baby brain, which is in the early stages of learning how to communicate with other humans. At that age, the "Crying for food equals I get food" lesson and bonding with mom are more important than the "Life is a cruel bitch that laughs at my desires" lesson that will inevitably be taught later.

They discovered that babies who snored displayed more behavior problems at ages 4 and 7, including aggressive, combative conduct and depression. By 7, a snoring baby was 1.5 times more likely to be a hyperactive, defiant monster child.

Dr. Karen Bonuck, the study's lead author, hypothesizes that snoring causes the baby to deliver more carbon dioxide to his or her brain than oxygen. Since the child is still forming neural connections, this could cross some of the wires in the emotional regulation and social conduct centers of the brain. Or maybe what you're misinterpreting as "snoring" is just the sound of the devils who have possessed your child growling in the night. It could go either way.

"The voices say that you've been a bad mommy. You must be ... 'corrected.'"

The researchers picked out 334 kids from schools that had a pretty homogenous socioeconomic enrollment set (so they could prevent winding up with a bunch of kids who were both small and stupid for some extraneous reason, like, say, they were malnourished due to their parents' crippling meth addiction).

Half of the kids selected were of lower-than-normal birth weight, and the others were normal or larger. At 8 years old, the kids were all given IQ tests. The researchers then examined all of their GCSE (a standardized test) scores when the kids had turned 20. The normal birth weight group not only scored higher on the IQ tests, but also scored an average of a half grade better on their GCSE tests than their less wind resistant classmates. They also completed more of the exam (the GCSE lets you choose which portions you take).

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Most go right to the "beer and balls" section, which has never been failed by a single participant.

The leader of the research team, Professor Peter Pharoah of the University of Liverpool, stresses that this doesn't mean that your gigantic freak mammoth baby is going to win a Nobel Prize. But nevertheless, science doesn't quite know how it works, though it does seem to contradict the cliche of the short, scrawny nerd outsmarting his ogrish jock classmates.

What we're trying to say is that for accuracy's sake, Bruce Banner should be bigger than the Hulk.

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"Dude, just piss him off so we can kick his ass."

Back in the '70s, some researchers in Dunedin, New Zealand, decided to examine a bunch of 3-year-olds to see whether they could predict future temperaments in kids who are still only old enough to drool on themselves and regard mundane objects with confused fascination. Observing the toddlers during independent 90-minute sessions, the researchers classified the kids as best they could as well-adjusted, reserved, confident, inhibited or "undercontrolled" (because you can't call toddlers "assholes").

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Which might be part of the reason so many of them are assholes.

Roughly 10 percent of the children were in that last category, which involved "lack of self-control, rapidly shifting emotions, impulsive and willful behavior and relatively high levels of negative feelings."

When they returned to study those kids at ages 21 and 32, the researchers discovered an unexpected side effect of their subjects' infant dickishness -- they didn't all wind up in jail, as might be expected, but scientists did find that when the "undercontrolled" kids grew up, they were twice as likely to have gambling problems as any other temperament classification.

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"You might have trouble picturing this, but I used to be a complete douchebag as a child."

Lead researcher Wendy Slutske cautions that just because your toddler is a mood-shifting jerk, that doesn't mean he or she is destined to be a compulsive gambler, but she suspects that some are born vulnerable to addiction. This would explain why some people can hit up a penny slot, win $100 and never gamble ever again, and others play until they're buried in the desert.

If you've ever screamed at a baby and the baby just stared back with hardcore steely resolve, just go ahead and teach him or her how to turn pacifiers into shanks, because, according to Adrian Raine, a University of Pennsylvania psychologist, a fearless baby is more likely to become a criminal as an adult.

Raine got his hands on a mental illness study from the 1970s that tested the fear responses of about 1,800 3-year-olds. The toddlers were exposed to two sets of sounds -- one was a neutral tone that was followed by nothing, and the other was a neutral tone followed by a shit-your-pants-terrifying wail. The toddlers quickly figured out when to expect the scary noise, and most of them sweated in response -- a normal fear reaction. Then again, there were some kids who showed no signs of fear at all.

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"Blast that noise at me again and see if I don't take off my hat and beat you to death with it."

In 2009, Raine checked in to see what the original test subjects had been doing with their lives, and found something fascinating. Along with everyone being a little fatter and uglier than they were when they were 3, Raine found that 137 of the test subjects had criminal records -- and not one of them had been among the group who had sweated during the fear study when they were 3.

The discovery was examined for any result-skewing factors such as race, gender and income, but more than anything else, the outstanding variable was that all of the convicted subjects had been fearless toddlers. This leaves us with an unsettling implication -- the possibility that some people are actually born criminals.

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"Rise and shine, you pukes. You got 30 minutes in the rec room, let's move."

Before you use this research to establish a Minority Report-style pre-emptive justice system, Raine notes that many other kids who also didn't show fear as babies went on to lead perfectly law-abiding lives. We would like to note that this only proves that they were never caught committing any crimes. Or maybe they grew up to be scientists who tormented 3-year-olds by blasting scary noises at them.

For more terrifying information on chi'ren, check out 6 Shockingly Evil Things Babies Are Capable Of and 5 Superpowers We All Had as Babies (According to Science).

If you're pressed for time and just looking for a quick fix, then check out Found at Your Local Library: The Three Stooges Book